CVE-2011-4505 in Speedtouch 5x6 Router
Summary
by MITRE
The UPnP IGD implementation on SpeedTouch 5x6 devices with firmware before 6.2.29 allows remote attackers to establish arbitrary port mappings by sending a UPnP AddPortMapping action in a SOAP request to the WAN interface, related to an "external forwarding" vulnerability.
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Analysis
by VulDB Data Team • 08/08/2024
The vulnerability identified as CVE-2011-4505 affects the Universal Plug and Play Internet Gateway Device implementation within SpeedTouch 5x6 series routers running firmware versions prior to 6.2.29. This represents a critical security flaw in the network device's handling of UPnP protocol requests, specifically within the Internet Gateway Device profile that governs how routers manage port forwarding and network address translation. The issue stems from insufficient validation mechanisms within the UPnP service implementation, allowing unauthorized remote actors to manipulate the device's port mapping configuration without proper authentication or authorization.
The technical flaw manifests through the absence of proper access controls and input validation when processing SOAP requests sent to the WAN interface of these devices. When a remote attacker crafts a malicious UPnP AddPortMapping action request, the device processes this without adequate verification of the requester's credentials or authorization level. This vulnerability falls under the CWE-284 access control weakness category, specifically addressing improper access control in network services. The UPnP IGD service operates on port 1900 and typically listens on the WAN interface, making it accessible from external networks without proper firewall restrictions.
The operational impact of this vulnerability extends beyond simple port mapping manipulation, as it enables attackers to establish arbitrary port forwarding rules that can expose internal network services to external threats. An attacker could potentially redirect traffic from external ports to internal vulnerable services, creating pathways for further network exploitation or establishing persistent backdoors. This vulnerability directly maps to ATT&CK technique T1098.002 which involves establishing persistence through additional cloud credentials, though in this case it involves establishing network persistence through port forwarding manipulation. The ability to create arbitrary port mappings effectively bypasses traditional network segmentation and firewall rules, allowing attackers to circumvent security controls that rely on port-based filtering.
The exploitation of this vulnerability requires minimal technical expertise and can be accomplished through automated tools that construct proper UPnP SOAP requests. The attack surface is particularly concerning for residential and small office environments where these devices are commonly deployed without proper network segmentation or monitoring. Network administrators should note that the vulnerability affects devices that may be running for years without firmware updates, particularly in environments where automatic updates are disabled or not properly configured. Organizations should consider implementing network monitoring to detect unusual UPnP activity and ensure that devices are updated to firmware versions that address this vulnerability, as the affected firmware versions likely contain multiple security weaknesses beyond this single port mapping issue.
Mitigation strategies should include immediate firmware updates to version 6.2.29 or later, which address the underlying access control deficiencies in the UPnP implementation. Network segmentation through proper firewall rules and disabling UPnP functionality where not required provides additional defense-in-depth measures. The use of network monitoring tools to detect unauthorized UPnP activity can help identify exploitation attempts, while regular vulnerability scanning should include checking for exposed UPnP services on WAN interfaces. Organizations should also consider implementing network access control policies that restrict external access to UPnP services and ensure that only authorized personnel have access to configure port forwarding rules on network devices.